program tc09();
var N,c:integer;
	function Fat (N:integer; var c:integer): integer;
	begin
		c:=c+1;
		if N > 0
		then Fat:= Fat (N-1,c) * N
		else Fat:= 1
	end
begin
	N:=3; c:=0;
	write (Fat(N,c));
end.